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The manufacturing method influences the properties of the produced components. This work investigates the influence of manufacturing methods, such as fused deposition modeling (3D printing) and injection molding, on the water absorption and mechanical and thermal properties of the specimens produced from neat bio-based poly(lactic acid) (PLA) polymer and poly(lactic acid)/wood composites. Acrylonitrile butadiene styrene (ABS) acts as the reference material due to its low water absorption and good functional properties. The printing layer thickness is one of the factors that affects the properties of a 3D-printed specimen. The investigation includes two different layer thicknesses (0.2 mm and 0.3 mm) while maintaining uniform overall thickness of the specimens across two manufacturing methods. 3D-printed specimens absorb significantly higher amounts of water than the injection-molded specimens, and the increase in the layer thickness of the 3D-printed specimens contributes to further increased water absorption. However, the swelling due to water absorption in 3D-printed specimens decreases upon increased layer thickness. The tensile, flexural, and impact properties of all of the specimens decrease after water absorption, while the properties improve upon decreasing the layer thickness. Higher porosity upon increasing the layer thickness is the predominant factor. The results from dynamic mechanical analysis and microscopy validate the outcomes. The results from this experimental study highlight the limitations of additive manufacturing. [ABSTRACT FROM AUTHOR]

• Microencapsulation of PCM with SiO 2 by Sol-gel process. • PCM@SiO2 incorporation effectively reduced concrete pavement surface temperatures, crucial for urban heat management. • Up to 30% PCM@SiO2 replacement maintained concrete strength within Indian standards, suitable for construction use. • Enhanced thermal energy storage capabilities were observed with increased PCM@SiO2 content. This study investigates the potential of enhancing thermal performance in pavement concrete by integrating microencapsulated phase change materials (PCM@SiO 2) using a Sol-gel process for encapsulation. With a concentration range from 0% to 20% in 5% increments, the effects of PCM@SiO 2 on both the mechanical strength and thermal performance of concrete were evaluated. Although the addition of PCM@SiO 2 resulted in a compromise in mechanical strength, significant improvements in thermal performance were observed, demonstrating a promising approach to mitigating temperature stresses and the urban heat island effect in pavement construction. This balance between mechanical and thermal properties underscores the potential of PCM incorporation as a strategic material choice for innovative urban development. [ABSTRACT FROM AUTHOR]

Carbide dispersion for reinforcement is an effective strategy to enhance the performance of tungsten (W). High-entropy carbides (HECs), when compared to conventional carbides, offer superior thermal stability, hardness, mechanical strength, creep resistance, and wear resistance. This study represents the first successful incorporation of (HfNbTaZr)C as a reinforcing phase into a W matrix, resulting in the formation of a W-HEC alloy. Compared to other carbides such as ZrC, HEC demonstrates improved coherency with the W matrix, resulting in a significant increase in plasticity and enhanced high-temperature stability. This innovative approach paves the way for alloy design in high-temperature applications such as nuclear fusion, providing fresh insights into the enhancement of mechanical properties and thermal stability. • A (HfNbTaZr)C HEC has been synthesized, for the first time, incorporated as a reinforcing phase into the W matrix. • The mismatch between HEC(200) and W(110) is 0.018, smaller than the W-ZrC alloy, indicating better coherence with the W matrix. • The W-HEC demonstrates outstanding plasticity at 600 °C, displaying total elongation of 33.0%, surpassing other W alloys. • The W-HEC hardness decreases is less than the W-ZrC after annealing at 1800 °C, demonstrating superior thermal stability. [ABSTRACT FROM AUTHOR]

In contemporary developments across automotive, aerospace, and military industries, there is an ever-growing demand for lightweight and robust polymer composites. In this study, a ductile epoxy resin, carbon nanotubes (CNTs), cellulose nanofibers (CNFs), and silica nanoparticles were used to fabricate nano-fillers/epoxy composites and nano-fillers/silk fibers/epoxy hybrid composites through solution casting and hot pressing. Their mechanical properties and thermal characteristics were analyzed and compared, which show that: these nano-fillers can dramatically enhance the strength and stiffness of the ductile epoxy resin; however, this is achieved at the expense of its toughness and extensibility. CNT/silk fiber/epoxy hybrid composite has the highest tensile strength (81.10 MPa), Young's modulus (3.76 GPa) and impact strength (103.7 kJ/m2), while the CNFs-reinforced one exhibits the highest breaking energy (9.96 MJ/m3). These nano-fillers almost do not affect the thermal stability of the epoxy resin and silk fiber composites. In addition, the fracture modes of their reinforced composites were revealed by macroscopic and microscopic observations. • Reveal how different nano-fillers affect the mechanical behaviors of ductile polymer matrix. • Explore the optimal content of these nano-fillers in the polymer matrix. • Indicate nano-fillers do not affect the thermal stability of their reinforced composites. • Elucidate the composites' fracture modes introduced by silk fibers and different nano-fillers. [ABSTRACT FROM AUTHOR]